JP5468614B2 - Printer table - Google Patents

Description

  The present invention relates to a substrate support device for a printer having a printer table or the like, for example, used in a flat bed printer. In the described embodiment, the table consists of a vacuum table for holding the substrate in the printer.

  It is well known that a vacuum table is used to support a substrate in a flat bed printer. In a common type of vacuum table, the table has a top surface for supporting the substrate to be printed. A plurality of holes are provided in the surface of the table, and the holes are connected to a negative pressure source. The substrate is placed on a table for printing, and the substrate covers a hole in the table surface. During printing, when negative pressure is applied, air is drawn through the holes in the table. Therefore, the negative pressure works, and the substrate is held on the table.

  However, problems can arise if the size of the substrate is smaller than the area occupied by the holes in the table. In such a situation, when the substrate is placed on a table, there are holes that are not covered by the substrate. It is disadvantageous to leave such uncovered holes intact during printing. This is because, in order to apply a sufficient negative pressure to hold the substrate to be printed on the table, it is necessary to operate the pressure source with a relatively high power compared to a configuration in which all the holes are covered. The more holes that are not covered, the greater the problem.

  Other problems can also occur if the holes remain uncovered during the printing operation. Open holes can cause high airflow near the printhead nozzles, which can interfere with printing and / or cause degradation in print quality.

  To improve this configuration, a mask is placed on the table to cover the holes that are not covered by the substrate. Such a mask is composed of, for example, paper, card, or plastic sheet material cut into an appropriate shape. In particular, when the area of the table that is not covered with the substrate is an irregular shape, the mask may be composed of a plurality of mask elements.

  Since the negative pressure applied during printing also serves to hold the mask on the table, satisfactory results may be obtained even if the mask is simply placed on the table. However, in practical applications, it is usually preferred to fix the mask to the table, particularly when similar substrate placements are used for successive printing operations. For example, when printing on the substrate is complete, it is normal practice for the pressure source to apply positive pressure to the holes in the table to assist in the removal of the printed substrate. Applying such positive pressure also has the effect of removing the mask, which is disadvantageous, especially when multiple substrates are printed using the same mask configuration.

  When the mask is made of a plastic sheet, an adhesive or adhesive backing may be provided to hold the mask on the surface. However, this may leave a sticky residue on the surface of the table. Also, such masks are not suitable for repeated use and removal from the table and have a limited lifetime.

  In particular, when the mask is made of paper or a card, the mask may be fixed at an appropriate position on the table using, for example, an adhesive tape. However, such taping is time consuming and adds considerable time to the print cycle.

  As a further problem, the tapes and / or adhesives used are often not resistant to the effects of radiation, such as UV radiation and / or heat exposed during the printing cycle. In particular, for masks that have been subjected to multiple printing cycles, this causes loss of adhesion between the tape or mask material and the table, and lifting and / or curling of the tape or mask material. there is a possibility. This in turn can cause degradation of print quality and / or stop of the print cycle to reattach the tape.

  When multiple sets of one or more substrates with similar shapes are printed using the same mask configuration, the mask is usually held on a table for printing multiple sets of the substrates. . This increases the risk that the tape holding the mask will be removed. Also, as described above, it is normal practice to use a pressure source to send air through the holes after the end of the printing operation to assist in the removal of the substrate. This practice can cause damage to the mask and / or increase the risk that a portion of the tape and / or mask will lift from the table.

  Attempts to overcome these problems led to a system in which multiple holes were placed in multiple areas of the table and the pressure applied to each area could be controlled independently. Therefore, in such a configuration, one or more pressure sources are selectively used so that negative pressure is applied only to the holes covered by the substrate, and negative pressure is applied to one or more areas. Added. However, experience with such systems indicates that the areas often do not correspond to the shape of the substrate being printed, and such systems often require masking. Also, the pressure supply mechanism greatly increases the complexity and cost of supporting the area.

  Aspects of the present invention seek to overcome or mitigate one or more of these and other problems.

  According to one aspect of the present invention, there is provided a substrate supporting apparatus for a printer, the table having a support surface for supporting the substrate during printing, wherein the support surface includes a plurality of substrate holes ( substrate apertures), means for applying negative pressure to the substrate holes to hold the substrate on the table, a plurality of mask apertures, and holding the mask on the support surface Means for applying a negative pressure to the mask hole, so that the pressure can be applied independently to the hole and the mask hole. An apparatus is provided.

  By providing a specific mask hole for holding the mask on the table, the need to tap the mask against the table can be eliminated. Since the pressure is applied separately to the substrate hole and the mask hole, the mask continues to be held on the table even when the negative pressure is released from the substrate hole to remove the substrate from the table.

  As described further below, preferably positive pressure is applied to the substrate holes independently of the mask holes. In some configurations, positive pressure is applied to the mask holes independently of the substrate holes.

  Preferably, the apparatus further includes a pressure source for applying pressure to the substrate hole and another pressure source for applying pressure to the mask hole. With such a configuration, the operation flexibility of the apparatus can be further increased, and the complexity of the pressure supply configuration can be reduced. In a preferred embodiment, each pressure source is adapted to apply a negative pressure to the substrate or mask as needed.

  Preferably, the mask hole is located in a table area different from the table area having the printed material hole. By having the mask holes spaced apart from each other, the negative pressure on the mask for holding the mask on the table can be maintained even when the negative pressure for holding the printing material on the table is eliminated.

  Preferably, the mask hole is located in the region of the support surface.

  Preferably, the mask hole is located in an end region of the table. In general, the substrate holes do not exist in the end region around the table. Preferably, a mask hole is present in a part or edge region around this. In some printer configurations, the edge region is configured about 1 inch (2.5 cm) around the table (or surrounding area).

  Preferably, the mask hole is located at one end of the table. In some configurations, it is preferred that the mask holes be present around the table or at the entire edge or at most. It may be desirable in some cases because more parts of the mask are held on the table and multiple masks can be held on the table. However, in some configurations it is preferred that the mask be held only at one end. For example, it may be advantageous in configurations where positive pressure is applied to the substrate holes during removal of the substrate. During this step, negative pressure is preferably applied to the mask holes to hold the mask on the table. By applying positive pressure to the substrate hole, the mask is lifted from the table in the area of the mask over the substrate hole. When the mask is held at a plurality or all of the end portions, there is a high possibility that the mask will be moved from that position. However, when the mask is held only at one end, the mask only lifts even if a positive pressure is applied to the hole to be printed. Since the mask is not pressed down so strongly, it is unlikely that the mask will be moved from that position.

  Generally, the substrate table is rectangular. It should be understood that if different shapes are used, the features described herein with respect to the rectangular table also apply to non-rectangular tables.

  Preferably, the end region having the mask hole is spaced from a reference element associated with the table. In some configurations, a reference point is provided at the corner or end of the table. Preferably, the mask holes are spaced from such points or elements so that the mask does not interfere with the reference element position.

  Preferably, the mask hole is located at the long end of the table. As mentioned above, the table is generally rectangular and preferably the mask holes are located at the long end of the rectangle.

  Preferably, the mask has one or more sheets made of plastic material.

  Preferably, the mask is made of a semi-rigid material. Preferably, the mask made of sheet material is substantially hard on the sheet surface. Preferably, the sheet material is resistant to being rolled, bent and / or folded when located on the support surface. The sheet material is at least partially self-supporting and may preferably be held substantially horizontally at the first end, the vertical deflection of the sheet being the angle of the sheet deflection (the held end). Is preferably less than 45 degrees, preferably less than 30 degrees, less than 20 degrees, or less than 10 degrees. In some configurations, the mask material is substantially rigid to the extent that there is substantially no vertical deflection of the sheet when held substantially horizontal at the edges.

  Preferably, the mask is semi-rigid to the extent that it can be deflected upward and downward on the table, but in such a case, the mask returns to the same position on the table substantially (preferably exactly). An example of a suitable material is a celluloid membrane. However, thin films, particularly stretchable films, such as LDPE films, will not be appropriate in most cases.

  Preferably, the sheet-like mask is resistant to deformation on the sheet surface.

  Preferably, the mask material is substantially heat resistant, for example at a temperature above 70 ° C., preferably above 100 ° C., preferably above 150 ° C.

  Preferably, the hardness of the material is maintained even at such high temperatures. During printing, the table is heated and / or the mask is exposed to heat from a printing device such as a lamp and / or dryer.

  The mask may be composed of, for example, a film or sheet containing a polymer material. Thermoplastic or thermosetting materials may be used. The mask may include, for example, acetate, cellulose acetate, polyester, polyethylene, polypropylene, or other suitable material. As an example, the mask may comprise a semi-rigid sheet of polyester material having a thickness of about 300 microns. The mask may contain fillers or additives, for example to improve the hardness of the material. For example, the mask may be composed of a composite material including reinforcing fibers or particles in a polymer matrix such as a resin.

  The mask may have a material other than the plastic material. For example, the mask may comprise paper, card, steel shim or other material. The mask may have a plurality of materials. The mask may have multiple elements having the same or different materials.

  The thickness of the material is preferably such that the desired mechanical properties of the mask are obtained. For example, the thickness may be less than 1 cm, less than 0.5 cm, or less than 0.3 cm.

  In some examples, the thickness of the mask material used is preferably similar to the thickness of the substrate to be printed. If the substrate is thin, the thin mask material is carefully selected so that in some instances it has sufficient hardness and is substantially insensitive to elevated temperatures. There must be. For thick materials, hardness and heat resistance requirements do not matter so much and a wide choice is available.

  Preferably, the upper surface of the mask (the surface opposite to the mask surface in contact with the table) is dark and / or substantially non-reflective. For example, if a UV lamp is used in the printing apparatus, it is preferable to minimize reflection from the mask. For example, the mask may be black or may have a black coating or layer on the surface of the mask.

  Preferably, the apparatus further comprises a mask receiving member for holding or receiving a plurality of mask elements. Preferably, the apparatus may have a plurality of masks for use with different substrate configurations. Such a mask is advantageously accommodated in the area of the table and is preferably adjacent to the end of the table having mask holes. For example, the mask is attached to the device or printer so that it is held at the end and rotated from the stowed position to a position on the table.

  The holes of the substrate and / or the mask may be provided in a plurality of areas.

  Preferably, the device is adapted for use in an ink jet printer. Preferably, the device is adapted for use in a flat bed printer. Preferably, the device is used in a digital printer.

  The present invention further includes a substrate support table for a printer having a support surface for supporting the substrate during printing, the support surface having a plurality of substrate holes, and further having a plurality of mask holes. A step of placing a mask element covering the mask hole and the substrate hole on the table, and a step of applying a negative pressure to the mask hole in order to hold the mask on the support surface. A step of placing a substrate covering the substrate hole on the table; and a step of applying a negative pressure for holding the substrate to the table to the substrate hole separately from a pressure applied to the mask hole. A method for masking a substrate support table is provided.

  The present invention extends substantially to the methods and / or apparatus described herein with reference to the drawings.

  Features in one aspect of the invention are applicable to other aspects of the invention, and can be applied in appropriate combinations. In particular, method aspects are applicable to apparatus aspects, and vice versa.

  Preferred features of the present invention will now be described in detail by way of example only with reference to the accompanying drawings.

It is a top view which shows roughly the flatbed printer structure containing a table. It is a top view which shows a part of to-be-printed object table. It is a top view of the edge part area | region containing a mask hole. as well as Another example of a pressure source configuration is shown. It is a top view which shows roughly the to-be-printed object table to which the to-be-printed object and the mask were attached.

  An example of a flatbed printer is schematically shown in FIG.

  FIG. 1 shows a flatbed printer 1 having a substrate table 2 that supports a substrate 3 for printing. The upper surface of the table that supports the substrate 3 is flat and substantially rectangular, and the lower surface (not shown) of the table 2 is mounted on a transport mechanism including a rail 4 that extends parallel to the support surface. A motor and associated mechanism is provided for moving the table 2 back and forth along the rail 4.

  The printing apparatus 5 is attached to a frame that extends upward from the substrate table 2 and extends perpendicular to the moving direction of the table 2 on the rail 4. The printing device 5 includes one or more printhead arrays and may include other devices such as radiation sources for curing curable inks, as known in the art.

  During printing, the table 2 reciprocates under the printing device 5 at high speed. It is important that the substrate 3 is held on the table so that it does not move relative to the table during printing. This is partly because the position of the substrate 3 is determined and checked with reference to the table position. Further, when the substrate is held flat on the table, there is an advantage that the upper surface to which the ink is attached becomes flat. When the substrate is lifted or wrinkled on the substrate on the table, the print quality of the image printed on the substrate can be reduced.

  Negative pressure is applied to the substrate to hold the substrate on the table. FIG. 2 shows the details of the table 2 where the top hole 10 can be seen. Other configurations are possible, but in the configuration shown, the holes are arranged in a substantially square grid. The holes extend through the top surface of the table 2 and are connected to a negative pressure source, for example, in a conventional manner. In general, the table is generally hollow so that air can flow through it.

  The hole 10 extends over the entire top surface of the table 2 except for an end region 12 that extends around the table without holes.

  As is common in flatbed printing systems, one corner of the table 2 is a reference corner 18 as will be described in detail below.

  As shown in FIG. 3, a row of mask holes 14 is provided in the mask holding portion 12 ′ of the end region 12. The mask hole 14 extends through the upper surface of the table and is connected to a negative pressure supply source. As described further below, negative pressure is applied to the mask holes 14 to hold the mask on the table.

  FIGS. 4 a and 4 b schematically show two configurations for applying negative pressure to the substrate hole 10 and the mask hole 14. In FIG. 4a, two different negative pressure sources 11 and 15 are provided. The source 11 is used to apply a negative pressure to the substrate hole 10, and the negative pressure source 15 can apply a negative pressure to the mask hole 14. In the configuration of FIG. 4b, one negative pressure source 13 connected to a routing device 17 is provided. By controlling the routing device 17, it is possible to individually control the negative pressure with respect to the substrate hole 10 and the mask hole 14.

  The configuration of FIG. 4a is preferred in many cases. This is because the use of two power supplies facilitates set-up and operation, and positive pressure can be easily applied to the substrate to assist with removal from the table 2 when printing is complete.

  FIG. 5 shows a table 2 on which three substrates 3, 3 ', 3' 'are arranged on the surface for printing. The substrates 3, 3 ′, 3 ″ are arranged on the table 2 at intervals according to the custom.

  The mask 16 formed of a plastic sheet is cut so as to have a shape corresponding to the shape of the region of the table 2 that is not covered with the printing materials 3, 3 ′, 3 ″. In this case, the mask 16 has a substantially comb shape. The mask may be prepared, for example, by cutting the sheet material using a cutting table, a known cutting table such as a cutting table from Zund Plotting Systems (UK) or a KONGSBERG cutting table from Esko NV. Users. good. Users of flatbed printers usually have a cutting table for finishing after printing, which is advantageously used also for preparing a mask.

  When the mask 16 is disposed at an appropriate position on the table 2, the mask 16 covers all of the printed material holes 10 not covered with the printed material, and extends to the mask holding portion 12 ′ in the end region 12, so that the mask 16 The shape covers all of the holes 14.

  If the negative pressure configuration of FIG. 4 a is used, during operation of the two negative pressure sources 11, 15, the negative pressure applied to the substrate hole 10 will cause both the substrate 3, 3 ′, 3 ″ and the mask 16. Is stored in the table. Further, the negative pressure applied to the mask hole 14 holds the mask 16 on the table 2.

  When the negative pressure applied to the substrate hole 10 is released, the substrate 3 is removed from the table, but the mask is held in place by the negative pressure applied to the mask hole 14 by the mask negative pressure source 15. to continue.

  In the example of the printing operation, the following steps may be performed.

Step 1—Placing the Mask The mask 16 is placed on the support surface of the table so as to cover some of the substrate holes 10 and at least some of the mask holes 14. Negative pressure is applied to the mask hole 14 and the mask is held in place. Conveniently, negative pressure is applied to the mask holes 14 only after the mask is in place.

Step 2—Placing the Substrate The substrate is placed on the table so as to cover some of the substrate holes 10 while maintaining the negative pressure applied to the mask holes 14. Negative pressure is applied to the substrate hole 10 to hold the substrate in place. Since the mask is also positioned over some of the substrate holes 10, the negative pressure applied thereto holds the mask in place.

Step 3-Printing Printing of the substrate is performed. A negative pressure is applied to the substrate hole 10 during printing. Since the mask is also held by the negative pressure applied to the substrate hole 10, the negative pressure on the mask hole 14 may be optionally released. However, in practice, negative pressure continues to be applied to the mask hole.

Step 4—Removal of Printed Substrate Negative pressure is applied to the mask hole 14 to hold the mask in place. Negative pressure on the substrate holes 10 is released and / or positive pressure is applied to at least some of the substrate holes 10 to assist in the removal of the printed substrate.

  If a substrate requiring similar mask construction is further printed, the mask negative pressure is maintained and steps 2-4 are repeated as necessary.

  In most cases, registration of the substrate and / or mask with respect to the table is important in order to perform accurate printing of the substrate.

  In the configuration shown in FIG. 5, the substrate 3 is matched with the reference corner 18. Further reference points may be provided, for example, to align the mask with the table and / or further substrate 3 ', 3' '.

  In a preferred configuration, particularly when two or more substrates are placed on the table, the mask is aligned with a reference point on the table and the substrate is aligned with the mask.

  When one substrate is placed on the table, in a preferred configuration, the substrate is aligned with a reference point and the mask is aligned with the substrate.

  Other configurations are possible.

  The mask may contain any suitable material. For example, when the mask is composed of a sheet made of a plastic material, the material is a polystyrene sheet having a thickness of 300 microns. Other materials can be used. Examples of preferred materials include thin plastic sheet materials.

  The mask may be, for example, disposable for a single use, or semi-disposable (eg, several uses), or usable during many printing cycles. In a preferred printer configuration, the plurality of masks are placed in or adjacent to the printer. The mask is selected from the available masks before the printing operation.

  The necessary mask shape is formed using, for example, a flat bed cutter. Computer data relating to the substrate to be printed can be used to calculate the required mask shape (s). The data obtained by the calculation is used to cut out an accurate shape from the plastic material.

  The negative pressure applied to the hole is, for example, 100 mBar.

  The pitch of the substrate holes 10 of the known table array is about 1 inch. The pitch of the mask holes may be smaller or the same, but in many instances is larger than the pitch of the substrate holes 10.

  Preferably, the pressure source for the mask holes 14 is selected so that it is not necessary to mask the mask holes 14 that are not used in a particular printing cycle. Therefore, a large vacuum pump is preferably used to apply a negative pressure to the mask hole 14.

  While the mask holes are expected to be incorporated into a new printer table, it is anticipated that the present elements will be attached to an existing printer. For example, the mask holes are provided as part of the elements installed on the printer table in the existing pudding configuration.

  Although the invention has been described above, it is to be understood that this is by way of example only and that details may be modified within the scope of the invention.

Each feature disclosed in the description and (where appropriate) the claims and drawings may be provided alone or in any appropriate combination.

Claims (14)

A substrate support device includes a substantially flat table having a support surface for supporting at least one substrate during printing, the support surface defining a printing area. is intended to, the table, the print region being adapted to print one or more of the substrate which partially covers the said table, a plurality of the substrate hole, the printing of the table to hold each of the printing object in the region, the holding means for applying a negative pressure to the substrate hole, and a plurality of mask hole located in spaced region from the print region, the mask to the support surface A flatbed printer having means for applying a negative pressure to the mask hole ,
And a substantially flat mask having a notch generally corresponding to each of the substrates, and covering at least one of the substrate holes not covered by the one or more substrates. Make the device
The mask is held by pressure applied to both the substrate hole and the mask hole;
A pressure can be applied independently to the substrate hole and the mask hole, and the mask is held on the table by the pressure applied to the mask hole, while the substrate from the support surface. The apparatus can be selectively removed .   The apparatus according to claim 1, further comprising a pressure source for applying pressure to the substrate hole and another pressure source for applying pressure to the mask hole.   An apparatus according to any preceding claim, wherein the mask hole is located in a region of the support surface.   The apparatus according to claim 1, wherein the mask hole is located in an end region of the table.   An apparatus according to any preceding claim, wherein the mask hole is located at one end of a table. 6. An apparatus according to claim 4 or claim 5 , wherein the end region having the mask hole is spaced from a reference element associated with the table. The mask holes, apparatus according to any one of claims 4 to 6, characterized in that located on the long end of the table.   An apparatus according to any preceding claim, wherein the mask comprises one or more sheets made of plastic.   An apparatus according to any preceding claim, wherein the mask is made of a semi-rigid material.   An apparatus according to any preceding claim, wherein the mask is substantially heat resistant at a temperature of 70 ° C.   An apparatus according to any preceding claim, wherein the surface of the mask is dark and / or substantially non-reflective.   An apparatus according to any preceding claim, further comprising a mask receiving member for receiving a plurality of mask elements.   Apparatus according to any of the preceding claims, characterized in that it is adapted for use in an ink jet printer. A substantially flat table including a support surface for supporting at least one substrate during printing, the support surface defining a print area, the table partially defining the print area; One or a plurality of printed materials covering the substrate are printed, and the support surface further includes a plurality of printed material holes and a plurality of mask holes located in a region separated from the printing region in the table. Having a method of masking a substrate support table for a flatbed printer,
A substantially flat mask element having a notch corresponding to each of the substrates and covering at least one substrate hole not covered by the mask hole and the one or more substrates ; Placing on the table;
Applying negative pressure to the mask hole to hold the mask on the support surface;
Placing at least one substrate to cover the substrate hole on the table;
Applying a negative pressure for holding the at least one substrate on the table to the substrate hole separately from the pressure applied to the mask hole ;
Holding the mask on the table by pressure applied to the mask hole, and selectively removing at least one substrate from the support surface .
A method for masking a substrate support table.

Images